Development of an Interface that Reproduces Walking Motion in VR Space: Study of Reducing the Delay of Reproduction Time

In this study, we develop an interface that reproduces the walking motion in Virtual Reality (VR) space. In order to reproduce the walking motion, we detected a user’s repetitive motion, called locomotion. Using the periodic of this locomotion, we reproduced a user’s walking motion in the VR space. We estimated the periodic from the movement of four joints by using the autocorrelation function. Based on the periodic, we reproduced the walking motion in VR space. However, this interface needs to measure stepping motion about 4 seconds to estimate periodic. Therefore, there is a delay time of approximately 4 s when this interface reproduces the walking motion to VR space. This delay is particularly evident when the user starts or stops walking. When this delay time is too long, the user may experience discomfort. In this study, to shorten this delay time, we examined the possibility of controlling the reproduction of the user’s starting and stopping motion based on the height of the knee. The results suggest that we can successfully shorten the delay time using proposed method. We also conducted an evaluation experiment to verify whether this interface is comfortable or not. By the result, interface was highly evaluated.